Consistent exercise has lasting health benefits. An exerciser's performance during a workout session depends on many factors including, for example, the exerciser's base line health status, nutritional habits, athletic skill, training regiment, etc. Such factors are the subject of much research. Often, an exerciser's physiological state may affect the quality and duration of an exercise or athletic performance event. Ideally, an exerciser would perform a workout at a time that optimizes his or her mental and physical state.